5
In the event of high limit switch operation, the appliance cannot
be restarted unless the water temperature is reduced to
approximately 120°F (49°C). The high limit reset button on the
front of the control then needs to be depressed.
Continued manual resetting of high limit control, preceded by
higher than usual water temperature is evidence of high limit
switch operation. The following is a possible reason for high
limit switch operation.
A malfunction in the thermostatic controls would allow the gas
valve to remain open causing water temperature to exceed the
thermostat setting. The water temperature would continue to
rise until high limit switch operation.
Contact your dealer or service agent if continued high limit
switch operation occurs.
FIGURE 3 - DIGITAL THERMOSTAT
ELECTRONIC IGNITION CONTROL
Each heater is equipped with a ignition module. The solid state
ignition control (Figure 4), ignites the main burner by utilizing a
silicone nitride ignitor. The silicone nitride ignitor shuts off during
the heating cycle and the main burner flame is sensed through
a remote flame sensor integral to the silicone nitride ignitor
assembly. The ignition control will try to ignite the main burner
three times before lockout. Then it waits one hour before trying
again to ignite the main burners. This is a continuous cycle.
FIGURE 4 - IGNITION CONTROL BOARD
EXHAUST INDUCER (BLOWER ASSEMBLY)
All units are equipped with a exhaust inducer. The inducer
assists in drawing in fresh air to the unit for combustion and
then assists in dispensing the combustion by-products into the
venting leading outside.
The exhaust inducer is equipped with a gravity controlled damper
to reduce the amount of heat loss through the flue, improving
efficiency.
FIGURE 5 - EXHAUST INDUCER
CIRCULATING PUMP
A circulating pump is used when a system requires a circulating
loop or there is a storage tank used in conjunction with the
heater. Refer to the piping diagrams at rear of manual for electrical
hookup information and install in accordance with the latest
version of the National Electric Code ANSI/NFPA No. 70.
Only all bronze circulators are used with commercial water
heaters.
Although circulators are oiled and operated by the manufacturer
some circulators must be oiled again before operating. Please
refer to manufacturer’s instructions.
DISHWASHING MACHINE REQUIREMENT
These appliances meet the National Sanitation Foundation
Standard for sanitary installations when used with the following
leg kits, Part No’s. 6570-0 and 6570-7.
All dishwashing machines meeting the National Sanitation
Foundation requirements are designed to operate with water
flow pressures between 15 and 25 psi. Flow pressures above
25 psi, or below 15 psi, will result in improperly sanitized dishes.
Where pressures are high, a water pressure reducing or flow
regulating control valve should be used in 180°F (82°C) line to
the dishwashing machine, and should be adjusted to deliver
water between these limits.
The National Sanitation Foundation also recommends
circulation of 180
0
F water. Where this is done, the circulation
should be very gentle so that it does not cause any unnecessary
turbulence inside the water heater. The circulation should be
just enough to provide 180
0
F water at the point of take-off to the
dishwashing machine. Adjust flow by means of the plug cock in
the circulating line.
